Steam-engine.



I. ALIEN, STEAM ENGINE. APPLICATION FILED Ame, .|911y ,Pmnted sept. 17,191s.

3 SHEETS-SHEE I.

IV i

B. T. ALLEN.

STEAM ENGINE. APPLICATION FILED Amb. 1911.

Patented spf. 17,1918.

3 SHEETSvSMEE 2."

B. T. ALLEN.

STEAM ENGINE.- APPLICATIQN Fll-Enwmifs; 19HV v 1,278,818. l PatentedSept. 17, 1911.8. s snszrs-snen a:

wim u wwhdoa and in the present construction )revision is made, wherebya counterfiow o thc steam dui-in the compression stroke may take placeinto a suitable storage 0r transfer duct,- such counterflow, however,being cut off at a point during the stroke of the engine at which it isdesired to trap the steam remaining in the cylinder for finalcompression. The steam in the storage or transfer passage vis admittedto the opposite end of the cylinder or on the opposite side of thepiston and mixes with the steam which is already uni dergoing expansionto perform useful work on the piston until the central exhaust ports areopened by the forward movement of the piston. Thisoycle of operations isrepeated in the reverse direction during-'the opposite movement of thepiston.

The arrangement of the valve mechanism for controlling the admission .ofsteam and for controlling the counterflow steam and for controlling theadmission of the counterlow steam to the opposite side ofthe piston ispreferably so constructed and propor tione'd that the counterfiow steamwill be compressed by the piston to a point which may approi'cimatelyequahthe pressure of the steam undergoing expansion at the instant whenthe compressed counterflow steam is admitted to `the cylinder. andcommingles with the expanding steam.

In the preferred constructon a` valve mechanism competent to .perfor theseveral functions 'conveniently takes the form of a balanced pistonvalveg and it may'emboddyl means whereby the valve .heads'are made ajusta'ble with relation to eachother and each head embodies meanswhereby it may be adjusted to vary the time of cutoil' and ad.

mission of the counterflow steam with relation to the time of admissionand cut oli' of the live steam.

i The valve shown is of the piston type and embodies two heads indicatedgenerally at O and O. These two heads are so.pos1

vproperly coperatie with the ortsm vleading to the end s of: the cyllners .andat all two end compartments-"T eend compel-t ments are incommunication Witlreach other.-

. How steamI is compressed until suchtime as the' valve maybe moved toclose the ports.

and to open the jp'orts vto the opprsite end of the cylinder. In orderthatprovision may be made vfor notonly changing the relation 'ordistancebetwoen the two' valve pistons, so-'as to regulate the 'periodof out oil' of live steam, but also to reg Iite-the period of cut offandV opening of' the ports mms-1s r locating-the piston O betweenad'ustable abut ents or 1ock nuts o', and by ormirig each v lve plston1n sections which are acl- 1, tab e with relation to eachother. A convnient and preferred arrangement is that shown lin Fig. 8, where it willbe seen that supplemental valve piston membersV O2 are mounted on themain piston members and are adapted to be adjusted with relation.thereto 'byl tension and compression lock screws R and R',respectively. The two valve piston members are each preferably providedwith the usual packing rings andl the total width or thickness of each'valve' piston is preferably greater than tli'ewidth'1 olthe'portslongitudinally of the axis of the valve. Thus, the ports are closed tothe -live steam before being opened for the 'tissage of counterflowsteam and by adjusting the:v

width or thickness. of the. valve the period during which the piston maybeI moved 1in' the final compresi-non of the steam in the cylinder andt-he timing of the opening of' the ports at the opposite end of thecylinder for the admission of the compressed counterilow steam may beaccurately re'liulated.l In the position shown in Fig. 25 -the pistonlhas reached the left hand extreme of itsmovement, the exhaust ports lareops J'e d to the right hand end of the cylinderad ;11ve" steam isentering through the ports. 'at'ithe left hand, end of-the cylir-ider,v-The valve moving toward the left and 'continues to' move toward theleft, as shown inFig. 3,'

while the 'piston advances During' thisl movement'of the piston theports" at the right hand end of the cylinder are Wide open to thecompression transfer chamber and duringthe movementy of the piston afterthe exhaust ports are closed steam from the right hand end of. the.cylindercountertlows into the transfegchambr; As shown .in 4,) thevalvlhas' n its reverse movement and closes 'the ports4 at the z lefthandlend ,of the cylinder, but thei'ports':` times they divide the valveohamberinto three compartments, namel' a central and' at the right handend remain open andthe steam o n the Working side of the piston be'-gins to operate expansively, while'steam, at Y.

the righ-t hand end-is still 'free to'counteif# ow into thetransfferjchamber. As shown in Fig; 5, the movementso the piston andvalve continuegthe ports*v at the right` hand end are, closedvcomp1etely,after which the nal compression takesplace at this end ofthe cy1inder, and the ports at'theleft, hand end are opened' to thetransfer chamber, thus ,permitting the steam fromfthe latteritoow.nr-and commingle" withtheisteam 11i-the lefty handendqof' -thecylinder, thereby performing useful work.

The movement in this di" rection continues until the partsfassume the v'psitlonshown i, lexhaust transfer passage connecting and formed '1n partby opposite ends of the valve chamber, of apiston controlling theopening and closing of .the exhaust. ports- When in 4proximity to theforward extremes of its movements, and a balanced piston valve workingin the valve chamber to control thecommunica tion of the inlet portswith the center and ends of the valve chamber, whereby live steam may beadmitted' to the cylinder and steam compressed by the piston transferredfrom one to the other of said admission ports.

6. In a steam engine as specified in claim '3, a balanced piston valvehaving sectionalY A valve pistons with means for adjusting the sectionsaxially of the valve to vary theV thickness of the valves forcontrolling the f relative time' of opening and closing communicationwith the transfer passage.

n In a steam engine* as specified in claim 3, a balanced slide valveembodying pistons mman 8. In a'steam yengine a's' speciedin claim 3, abalanced'slidevalve embodying sectionalI f valve pistons adjustabletoward and awvay: from each other," and means for a'dynstlng -thesections axially of the valvcuto v vaiythe` thickness of the valves.

9. In' a steam engine, the-combination with y adjnstabletowardf'andzfrom eachl other vary' theadmissi on and out oflt thecylinder,

a cylinder having steanadrnis'sion ports at y its ends, exhaust`)ortsintermediate the ends, l

a transfer' cham' er extending-between' the admission ports and a pistonworking 'in' the cylinder betweenl the admission ports tandcontrol'ling"the opening' and closing ofthe l'exhaust 'ports when inproximityfto the' forward extremes of its.movementsv zof a `valvemechanlsm controllmg the admlssion 'of live other of the admissionports.1 'BENJl rl". ALLEN.'

40 steam to the cylinder a-nd` adj\1stab'ly een- I e trolling the flowof steamv from one to the'

